This PhD-thesis describes the design of efficient enzyme preparations for the hydrolysis of plant cell wall polysaccharides from corn silage. The application of enzyme preparations enables an increased utilization of plant feedstocks for biogas production. As the hydrolysis of xylan is a rate limiting factor in the anaerobic fermentation process, hemicellulolytic enzyme preparations can be used in biogas production plants to overcome such limiting effects.
This study addresses recalcitrance properties of xylan, rendering feedstocks resistant towards the enzymatic degradation. The design and development of an enzyme preparation, outperforming commercial available enzyme solutions and enabling an efficient conversion of corn silage to fermentable sugars, is described. An acetyl xylan esterase responsible for the increased efficiency of the enzyme cocktail was (cloned and) purified and characterised in detail. The mode of action of this enzyme was compared with 6 other acetyl esterases, classified as belonging to different carbohydrate esterase families.